1. Field of the Invention
The present invention relates to a two-color copying machine employing two ink donor sheets of different recording colors for recording data in two colors on a recording sheet of paper. The ink donor sheets are thermal-transfer-type recording mediums.
2. Description of the Prior Art
Many document materials and pamphlets are printed in two colors such as red and black. One purpose of using two colors is to highlight some items. Two-color copying machines utilizing electrostatic photography have been available. These two-color copying machines employ two electrostatic recording drums or sheets upon which electrostatic latent images are respectively formed. The latent images are developed with toner of respective colors. The two toner images thus produced are then transferred and thermally fixed to a recording sheet to finally produce a recorded image.
The conventional two-color copying machine can produce a number of copies by repeatedly exposing a single original, but consumes a large amount of electric power when fixing the toner images to the recording sheet. Since a large amount of heat is radiated from the fixing device, a heat insulator mechanism and an exhaust mechanism are required to protect other circuit components from the heat radiation. This causes the copying machine to be large and expensive to manufacture